In the preceding section we saw that in order to find good re-embeddings
of a polynomial ideal, we may try to find a tuple of indeterminates \(Z\) 
and a \(Z\) -separating term ordering for \(I\) . The possible choices of term
orderings leading to distinct reduced Gröbner bases of \(I\)  are
classified by the Gröbner fan of \(I\) , introduced and studied first in [1]}.
Here we want to classify the possible choices of \(Z\) -separating term orderings
leading to distinct reduced Gröbner bases of \(I\) .
